Tuesday, March 27, 2012

Humectants: Panthenol - a closer look

If you've read this blog for any length of time, you'll know I'm a fan of panthenol and use it in many different products. We see it a lot in hair care products, but I think it has a place in skin care products, especially those for dry or wounded skin. Allow me to share...

D-panthenol is the alcoholic analogue of pantothenic acid, or Vitamin B5. (Remember, alcohol doesn't mean the stuff we drink, it's an organic chemistry functional group. Look at those OH or hydroxyl groups!) "Animals require pantothenic acid to synthesize coenzyme-A (CoA), as well as to synthesize and metabolize proteins, carbohydrates, and fats." (Wikipedia) What we purchase at our suppliers is D-panthenol or DL-panthenol (DL-panthenol tends to be what we see in powdered form). It is well absorbed by our skin and rapidly converted to Vitamin B5 in our body. Pantothenic acid "appears to be essential to normal epithelial function..." (page 428, this paper)

It is water and alcohol soluble, but practically insoluble in fats, so we will be using this in water based or emulsified products, and not in anhydrous products. The suggested usage is 1% to 5% and you'll be using it in the cool down phase (liquid) or heated water phase (powder). It is approved by the FDA at 2% to be in anti-itching and wound healing products, although you can't make that claim. It is considered atoxic, meaning there should be no side effects from using it as it is something our body produces. It is also considered a penetration enhancer.

What are the claims about D-panthenol?
  • Improves stratum corneum hydration
  • Reduces redness and inflammation
  • Increases wound healing by stimulating skin epithelialization
  • Improves skin barrier mechanism repair
  • Mitigates itching and soothes irritation
  • Behaves as a humectant
Wow! That's one heck of a list for an ingredient that we use at 2% to 5% in the heated phase (powder) or the cool down phase (liquid) of our water based or emulsified products!

Panthenol improves the hydration of our stratum corneum by behaving as a humectant (page 31, this paper, or p 428, this paper), so it draws water from the atmosophere to our skin. This increases skin's elasticity and softness. This means our skin will feel less dry and we'll see less cracking or flaking. One study reported that treatment with a panthenol ointment for 7 days improved the stratum corneum's hydration and reduced transepidermal water loss (page 679, this paper)

Although an experiment using 4.2% panthenol ointment did not protect against inflammation and redness from sun exposure (p. 429, this paper), it has been demonstrated that it can be used in after sun formulations to relieve redness and inflammation (page 333, Barel Handbook of Cosmetic Science & Technology, 3rd edtion). It can be used to alleviate dry or inflamed skin caused by SLS induced irritation (in experiments) and for people who have to wash their hands very frequently, and it can be used in advance to reduce future irritation and reduce injury to skin's barrier mechanisms (p 430, this paper)

In our hair, as little as 2% in an aqueous solution has shown an increase of up to 10% in the diameter of our hair (Handbook, 3rd edition, page 113).

Studies have shown that 2% to 5% panthenol ointment can increase the healing of wounds caused by skin transplants or scar treatment, diaper rash, and leg ulcers (page 429 to 430, this paper). Panthenol has been shown to activate fibroblast proliferation, which is a major part of wound healing. (It's suggested that we keep wounds moist!)

For more information on wound healing, click here for Anthony Dweck's paper on the topic

"In sodium lauryl-sulphate-induced irritated skin, panthenol has been found to promote skin barrier repair and SC (stratum corneum) hydration." (page 678, this paper)

I feel satisfied seeing all the science behind these claims, but there's one small drawback. Most of these results have been found while using an ointment or water-in-oil product. We make oil-in-water products, so we aren't going to see the same results. One study showed a reduction in absorption of panthenol when it was administered to the skin in olive oil, which showed you that the type of product in which you add the panthenol is just as important as the panthenol itself. So you might want to consider using the higher amount of panthenol - 5% - rather than lower levels in oil-in-water emulsions or any other product (say a cleanser or toner).

Join me tomorrow as we take a look at some other benefits of using humectants!


Kate said...

Love the comment about alcohol being a functional group not just an adult beverage. I'm a chemist for a tween/teen lip products company and we had a customer call in berating us for putting ALCOHOL in a product for kids. The alcohol she was so worried about? Cetyl alcohol. It didn't matter how many times or in what way I tried to explain it- she could not comprehend that cetyl alcohol was not going to get her child drunk.

Veronique said...

Is there a big difference between the powdered and liquid one? Cause the 2 different suppliers I use have them (one has liquid one powdered) Is it just a preference thing? Thanks!

Danielle said...

Hi Susan,

I've been trying to figure out how most panthenol is made? Is it chemically synthesized or is it derived from plant material? I saw something that said it was made from honey but didn't back that up.

Robin said...

Would this be calc as part of water percent I lotion recipe.

Robin said...

Oops in lotion recipe?

Susan Barclay-Nichols said...

Hi Robin! Yes, anything water soluble is considered as part of the water percentage. Anything oil soluble is considered as part of the oil percentage.

Unknown said...

If using a powder is it recommended to pre mix with some of the water in the recipe before incorporating. Thanks.
Posted by Robin

Anonymous said...

Is this a natural product, or lab created?

Susan Barclay-Nichols said...

Sorry, I don't think I understand your question. Panthenol is Vitamin B5, which can be naturally occurring. It can be synthesized in a lab or in nature, like most vitamins. You can create Vitamin C in a lab or in an orange. In the end, it's still the same molecule and you couldn't tell the difference.

Crystena said...

What's the difference between a water in oil product and an oil in water product?

Susan Barclay-Nichols said...

Hi Crystena! Take a look at the newbie section to learn more about how we define our products!

Anonymous said...

Hi there, we have been using panthenol 75% in our body lotions and have now run out! We have the powder form dl -panthenol, could you tell me if we make this solution 25% powder and 75% water?



Debra Leroy said...

Can you put DL-Panthenol in bath salts and if so how much thank you!

Debra Leroy said...

Can you Email me at trufflechic@gmail.com about the DL-Panthenol in bath salts

Susan Barclay-Nichols said...

Hi John! My suggestion is to ask your supplier and make a test batch to see what happens. I'm afraid I can't offer much information without knowing your exact recipe in percentages.

Hi Debra. I guess the question would be...why would you want to add it to bath salts? The second question is whether it could be added to bath salts? Salts tend to dissolve in water. And panthenol is water soluble.

I'm not emaling you as I would hope you would subscribe to this thread and come back to see the answer. Plus, when it's posted here, everyone benefits and that's a better use of my time.